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hypermetropia (long-sightedness) (hy-per-mi-troh-piă) n. the condition in which parallel light rays are brought to a focus behind the retina when the accommodation is relaxed. Normal vision can be restored by wearing spectacles with convex lenses (see illustration). Compare emmetropia, myopia.

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hypermetropia (hyperopia) Long-sightedness. A vision defect in which the lens of the eye is unable to accommodate sufficiently to throw the image of near objects onto the retina. It is caused usually by shortness of the eyeball rather than any fault in the lens system. The subject requires spectacles with converging lenses to bring the image from behind the retina back on to its surface (see illustration).